Production of dilute acids



mil 7,, 19360 F. A. HENGLEIIN ET AL 299369412 PRODUCTION OF DILUTE ACIDSFiled March 15, 1933 Patented Apr. 7, 1936 UNITED STATES PATENT OFFIQEFriedrich Wilhelm Stauf, Leverkusen-Wiesdorf, Germany, assignors to I.G. Farbenindustrie Aktiengesellschaft, Frankfort on the- Main, GermanyApplication March 15,

In Germany 1 Claim.

This invention relates to metallic containers being filled with acidforming substances, which containers are punctured and brought intowater whereby solutions containing a free acid are 5 formed.

Dilute acids are used for many purposes, thus for instance, in metalpickling processes, for the preservation of green-fodder, as accumulatoracid, etc. The working with concentrated liquid acids is, however, verydangerous inasmuch as unskilled workmen not being used to handle acids,can easily burn or poison themselves, especially since the dilution ofacids with water calls for especial precaution. Therefore it has beenaimed at providing acids in such a form that they can be handled withoutany danger.

In accordance with the present invention dilute acids are preparedwithout danger when substances yielding upon reaction with water acids,as for instance, sulfuric acid, hydrochloric acid, acetic acid, such asfor instance, sulfur trioxide, fuming sulfuric acid, pyrosulfuric acid,chlorosulfonic acid, thionylchloride and sulfuryl chloride, acetylchloride, titanium tetrachloride, silicon tetrachloride, stannictetrachloride, are filled into metallic containers, and the containersare brought into water after having been punctured.

As packing material not only sheet copper and leaded sheet iron haveproved suitable but also ordinary sheet iron, for instance, tin plateand black plate may find application, provided, the cover of thecontainer is tightly closed, for instance, by welding or folding. Suchclosure is tight against moisture and air and can be made especiallytight when working into the folding during this process for instancelead, caoutchouc, asphalt, etc. The means for tightening can also beobtained by squirting the tightening material upon the rim of the coveror bottom or also by applying massive packing rings. The content of thecontainer is dissolved by placing it into water after it has beenpunctured at different places shortly before use. Preferably thecontainer is weighted so that it remains on the bottom of the reservoir.

In thismanner acid solutions of any desired concentration can easily beobtained. Also solutions containing several acids are obtainable in thesame manner when using, for instance, chlorosulfonic acid and sulfurylchloride. The solutions obtained can be employed for all industrial andalso other purposes, for instance, in the preparation of green-fodder.

The accompanying drawing illustrates in front 1933, Serial No. 660,888March 24, 1932 elevation, with a portion broken away to expose theinterior, an embodiment of the invention.

The receptacle illustrated by the drawing is constructed of two metalsheets which are welded or folded together at the ends by suitablemeans. One part of metal sheet forming the front side of the receptacleis broken away to show that the receptacle is filled with an acidproducing compound which is indicated by points in the drawing. Thereceptacle illustrated by the drawing shows a flat shape, however, itmay have every shape suitable for the purpose in question.

The invention is further illustrated by the following examples withoutbeing restricted thereto:-

Example 1.-A black plate container filled with 5 kgs. of sulfur trioxideand tightly closed by electric welding is punctured at some places. Aweight of about 3 kgs. is attached thereto and the container is broughtinto 94-. liters of water. The water reacts with the sulfur trioxideinside the container with a buzzing noise. From the perforations adilute sulfuric acid escapes which mixes with the water yielding therebya 6% aqueous sulfuric acid solution, suitable for metal picklingprocesses.

Example 2.A tightly folded tin plate container containing 13.5 kgs. ofsulfuryl chloride is punctured at several places and, after weighting,is brought into liters of water. The reaction and dissolution of thecontent proceed in the same manner as indicated in Example 1, and anaqueous solution containing 9.6 grams of sulfuric acid per liter and 7.3grams of hydrochloric acid per liter is obtained, which can directly beused for the preservation of green-fodder.

Example 3.4.6 kgs. of chlorosulfonic acid are packed in a tin can. Theweighted container is punctured at several places and thrown into 100liters of water. A solution containing 14.6 grams of hydrochloric acidand 39.2 grams of sulfuric acid in one liter is thus obtained.

We claim:

Process of preparing aqueous solutions containing sulfuric acid,consisting in puncturing a tightly closed metallic container containinga substance which contains free sulfur trioxide selected from the groupconsisting of sulfur trioxide, fuming sulfuric acid, pyrosulfuric acidand chlorosulfonic acid and bringing the punctured 50 container intowater.

FRIEDRICH AUGUST HENGLEIN. FRIEDRICH WILHELM STAUF.

